docs: def get_fieldmap(self, path, return_list=False):
          """ Get fieldmap(s) for specified path. """
          fieldmaps = self._get_fieldmaps(path)
  
          if return_list:
              return fieldmaps
          else:
              if len(fieldmaps) == 1:
                  return fieldmaps[0]
              elif len(fieldmaps) > 1:
                  raise ValueError("More than one fieldmap found, but the "
                                   "'return_list' argument was set to False. "
                                   "Either ensure that there is only one "
                                   "fieldmap for this image, or set the "
                                   "'return_list' argument to True and handle "
                                   "the result as a list.")
              else:  # len(fieldmaps) == 0
                  return None